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1.
Inorg Chem ; 63(16): 7473-7492, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38591749

RESUMO

Halide exchange of (Cp3tms)2ThCl2 (1; Cp3tms = η5-1,2,4-(Me3Si)3C5H2) with Me3SiI furnishes (Cp3tms)2ThI2 (2), which is then reduced with potassium graphite (KC8) in the presence of 2,2'-bipyridine to give the thorium bipyridyl metallocene (Cp3tms)2Th(bipy) (3) in good yield. Complex 3 was fully characterized and readily reacted with various small molecules. For example, 3 may serve as a synthetic equivalent for the (Cp3tms)2Th(II) fragment when exposed to CuI, Ph2S2, organic azides, and CS2. Moreover, upon the addition of thiobenzophenone Ph2CS, p-methylbenzaldehyde (p-MeC6H4)CHO, benzophenone Ph2CO, amidate PhCONH(p-tolyl), seleno-ketone (p,p'-dimethoxy), selenobenzophenone (p-MeOPh)2CSe, di(p-tolyl)methanimine (p-tolyl)2C═NH, 1,2-di(benzylidene)hydrazine (PhCH═N)2, and nitriles PhCN, PhCH2CN, and Ph2CHCN C-C coupling results to give (Cp3tms)2Th[(bipy)(Ph2CS)] (8), (Cp3tms)2Th[(bipy)(p-MePhCHO)] (9), (Cp3tms)2Th[(bipy)(Ph2CO)] (10), (Cp3tms)2Th[(bipy){(p-tolylNH)(Ph)CO}] (11), (Cp3tms)2Th[(bipy){(p-MeOPh)2CSe}] (12), (Cp3tms)2Th[(bipy){(p-tolyl)2CNH}] (13), (Cp3tms)2Th[(bipy)(PhCHNN═CHPh)] (14), (Cp3tms)2Th[(bipy)(PhCN)] (16), (Cp3tms)2Th[(bipy)(PhCH2CN)] (17), and (Cp3tms)2Th[(bipy)(Ph2CHCN)] (18), respectively. However, when thiazole is added to 3, the dimeric sulfido complex [(Cp3tms)2Th]2[µ-(bipy)CH2NCHCHS]2 (15) can be isolated. Moreover, the addition of isonitriles such as Me3CNC and PhCH2NC to 3 results in C-N bond cleavage and C-C coupling processes to form the thorium isocyanido amido complexes (Cp3tms)2Th[4-(Me3C)bipy](NC) (19) and (Cp3tms)2Th[4-(PhCH2)bipy](NC) (20), respectively. Nevertheless, upon exposure of 3 to (trimethylsilyl)diazomethane Me3SiCHN2, the bis-amido complex (Cp3tms)2Th[5,6-(Me3SiCH)bipy] (21), concomitant with N2 release, is isolated.

2.
Transfus Apher Sci ; 63(4): 103964, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38959809

RESUMO

BACKGROUND: Platelet plays a vital role in both physiological and pathological processes. However, the limited storage time of platelet in vitro poses an immense challenge for its applications because of the increased risk of bacterial contamination and platelet storage lesions. Agitation can inhibit lesions by facilitating continuous oxygenation of platelets and permitting excess carbon dioxide to be removed during storage. However, it is still not known whether agitating BCs gives a positive effect on platelet quality. OBJECTIVES: To evaluate the quality difference between platelet concentrates (PCs) from buffy coats (BCs) held rest and agitation. METHODS: Samples were withdrawn for cell count, blood gas analysis, free hemoglobin level, hypotonic shock response, maximum aggregation rate, activation marker expression (CD62P and CD42b) and coagulation function. RESULTS: We found the PCs prepared from the agitating BCs had fewer residual WBCs, exhibited a better gas exchange ability, slower metabolism (higher pH, higher content glucose, and lower lactic acid levels), better hypotonic shock response, and lower levels of CD62P. The TEG-PC assays showed no difference in coagulation function. CONCLUSION: Our findings showed that BC can be agitated overnight before a soft spin.

3.
Proc Natl Acad Sci U S A ; 118(20)2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-33990466

RESUMO

Real-world decisions are often open ended, with goals, choice options, or evaluation criteria conceived by decision-makers themselves. Critically, the quality of decisions may heavily rely on the generation of options, as failure to generate promising options limits, or even eliminates, the opportunity for choosing them. This core aspect of problem structuring, however, is largely absent from classical models of decision-making, thereby restricting their predictive scope. Here, we take a step toward addressing this issue by developing a neurally inspired cognitive model of a class of ill-structured decisions in which choice options must be self-generated. Specifically, using a model in which semantic memory retrieval is assumed to constrain the set of options available during valuation, we generate highly accurate out-of-sample predictions of choices across multiple categories of goods. Our model significantly and substantially outperforms models that only account for valuation or retrieval in isolation or those that make alternative mechanistic assumptions regarding their interaction. Furthermore, using neuroimaging, we confirm our core assumption regarding the engagement of, and interaction between, semantic memory retrieval and valuation processes. Together, these results provide a neurally grounded and mechanistic account of decisions with self-generated options, representing a step toward unraveling cognitive mechanisms underlying adaptive decision-making in the real world.


Assuntos
Encéfalo/fisiologia , Comportamento de Escolha/fisiologia , Cognição/fisiologia , Tomada de Decisões/fisiologia , Modelos Neurológicos , Adulto , Encéfalo/anatomia & histologia , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Neuroimagem , Web Semântica
4.
Inorg Chem ; 61(16): 6234-6251, 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35413191

RESUMO

The uranium bipyridyl metallocene, [η5-1,3-(Me3Si)2C5H3]2U(bipy) (2), is readily accessible in good yield by adding potassium graphite (KC8) to a mixture of [η5-1,3-(Me3Si)2C5H3]2UCl2 (1) and 2,2'-bipyridine. Compound 2 was fully characterized and employed for small-molecule activation. It has been demonstrated that 2 may serve as a synthon for [η5-1,3-(Me3Si)2C5H3]2U(II) fragment in the presence of Ph2E2 (E = S, Se), alkynes, and a variety of hetero-unsaturated molecules such as diazabutadienes, azine (Ph2C═N)2, o-benzoquinone, pyridine N-oxide, CS2, isothiocyanates, and organic azides. However, upon exposure of 2 to thio-ketone Ph2CS, aldehyde p-MePhCHO, ketone Ph2CO, imine PhCH═NPh, azine (PhCH═N)2, and nitrile PhCN, it may also promote C-C coupling reactions forming [η5-1,3-(Me3Si)2C5H3]2U[(bipy)(Ph2CS)] (16), [η5-1,3-(Me3Si)2C5H3]2U[(bipy)(p-MePhCHO)] (17), [η5-1,3-(Me3Si)2C5H3]2U[(bipy)(Ph2CO)] (18), [η5-1,3-(Me3Si)2C5H3]2U[(bipy)(PhCHNPh)] (19), [η5-1,3-(Me3Si)2C5H3]2U[(bipy)(PhCHNN═CHPh)] (20), and [η5-1,3-(Me3Si)2C5H3]2U[(N2C10H7C(Ph)NH)] (22), respectively, in quantitative conversion. Furthermore, in the presence of CuI, a single-electron transfer (SET) process is observed to yield the uranium(III) iodide complex [η5-1,3-(Me3Si)2C5H3]2U(I)(bipy) (15).

5.
Inorg Chem ; 59(19): 14549-14563, 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-32975413

RESUMO

A Lewis base supported terminal uranium phosphinidene, [η5-1,3-(Me3C)2C5H3]2U(═P-2,4,6-tBu3C6H2)(OPMe3) (5), is isolated from the reaction of the uranium methyl chloride [η5-1,3-(Me3C)2C5H3]2U(Cl)Me (4) with 2,4,6-(Me3C)3C6H2PHK in toluene in the presence of Me3PO. Moreover, the reactivity of uranium phospinidene 5 toward a series of small molecules was comprehensively explored. While no reactivity of 5 with internal alkynes is observed attributed to steric hindrance, it readily reacts in good yields with various small molecules including isothiocyanates, aldehydes, imines, diazenes, carbodiimides, nitriles, isonitriles, and organic azides, yielding uranium sulfidos, oxidos, metallaheterocycles, and imido complexes.

6.
Transfus Med ; 30(1): 51-60, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31823441

RESUMO

OBJECTIVES: A novel pathogen reduction technique based on vacuum ultraviolet (VUV) irradiation was developed to reduce pathogen numbers in red blood cell (RBC) components. BACKGROUND: Contaminated blood components pose a great risk of infection in blood recipients. The continuous development of blood screening techniques and pathogen inactivating systems has significantly reduced this risk, but many limitations remain. METHODS: Escherichia coli and Bacillus cereus, and bacteriophage (BP) and Lentivirus (LV) were spiked into suspended red blood cells (sRBCs) or plasma. VUV light with maximum emission at 185 nm and an average dosage of 164 µW/cm2 was placed 5 cm above the targeted products to reduce the pathogen numbers. RESULTS: Treatment for 5 minutes was effective; 3 and 10 log reductions of E coli counts were observed in sRBCs and plasma, and 2 and 3 log reductions of B cereus counts were observed in sRBCs and plasma, respectively. The BP titre was reduced by two and five log points in sRBCs and plasma, respectively; the LV titre was reduced by at least three log points in both sRBCs and plasma. VUV-based irradiation of RBCs does not cause significant structural and functional harmful effects. This novel strategy provides moderate photonic energy to generate oxygen radicals from H2 O and O2 and to selectively decrease DNA integrity of the potential pathogens. CONCLUSION: The VUV-based pathogen reduction technique is a simple and fast procedure with high pathogen reduction efficacy, low toxicity and limited adverse effects on cellular blood products.


Assuntos
Bacillus cereus/crescimento & desenvolvimento , Desinfecção , Eritrócitos , Escherichia coli/crescimento & desenvolvimento , Lentivirus/crescimento & desenvolvimento , Espécies Reativas de Oxigênio/química , Raios Ultravioleta , Eritrócitos/microbiologia , Eritrócitos/virologia , Humanos , Ácidos Nucleicos/metabolismo
7.
Transfus Med Hemother ; 47(4): 337-343, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32884506

RESUMO

INTRODUCTION: Postpartum hemorrhage (PPH) is associated with maternal morbidity and mortality. Accurate diagnosis of the cause of puerperal hemorrhage is as important as treatment strategies for resuscitation. We report a case of coagulation disorder caused by endogenous heparin-like substances in a PPH patient. CASE PRESENTATION: A 30-year-old woman with no medical history of bleeding disorders suffered intractable hemorrhage following spontaneous delivery in a local hospital. The patient was transferred to the department of obstetrics of a superior hospital. On arrival, the patient was found to have severe hemorrhagic anemia, hemorrhagic shock, and disseminated intravascular coagulation. Active treatments were performed, but the patient continued bleeding. Laboratory testing, performed during early treatment, revealed that all coagulation factors were below normal. The differences between CK-TEG R-time (reaction time in citrated kaolin thromboelastography assay) and CKH-TEG R-time (reaction time in citrated kaolin with heparinase thromboelastography assay) suggested the presence of heparin activity. However, the patient's family denied heparin use prior to presentation. Thus, we deduced that endogenous heparin-like substances were the main cause of the coagulopathy. After receiving treatment with protamine, the patient stopped bleeding. Meanwhile, all coagulation parameters and the TEG assay results improved. CONCLUSIONS: In this case report, TEG assay suggested the presence of heparin activity in a PPH patient, and treatment also highlighted the importance of analyzing different parameters in TEG.

8.
J Cell Physiol ; 234(12): 22833-22844, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31264213

RESUMO

Conventional storage conditions of erythrocytes cause storage lesions. We propose that hypoxic storage conditions, involving removal of oxygen and replacement with helium, the changes in stored erythrocytes under hypoxic condition were observed and assessed. Erythrocytes were divided into two equal parts, then stored in conventional and hypoxic conditions, separately. Blood gas analysis, hemorheology, and hemolysis were performed once a week. Energy metabolism and membrane damage were monitored by enzyme-linked immunosorbent assay. Phosphatidylserine exposure was measured by flow cytometry. P50 was measured and the oxygen dissociation curve (ODC) plotted accordingly. Erythrocyte morphology was observed microscopically. In the 9th week of storage, the hemolysis of the hypoxia group was 0.7%; lower (p < .05) than that of the control group and still below the threshold of quality requirements. The dissolved oxygen and pO2 were only 1/4 of that in the control group (p < .01); the adenosine triphosphate, glucose, and lactic acid levels were decreased (p < .05), while the 2,3-diphosphoglycerate levels were increased relative to that in the control group (p < .01). There were no statistically significant differences in membrane damage, deformability, and aggregation between the two groups. In addition, the ODC of the two groups was shifted to the left but this difference was not statistically different. Basically similar to the effect of completely anaerobic conditions. Erythrocytes stored under hypoxic conditions could maintain a relatively stable state with a significant decrease in hemolysis, reduction of storage lesions, and an increase in shelf-life.


Assuntos
Preservação de Sangue , Eritrócitos/metabolismo , Hélio/sangue , Oxigênio/sangue , Adulto , Hipóxia Celular , Sobrevivência Celular , Metabolismo Energético , Deformação Eritrocítica , Eritrócitos/patologia , Feminino , Hemólise , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Adulto Jovem
9.
Platelets ; 30(3): 403-412, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29595346

RESUMO

Cryopreservation can slow down the metabolism and decrease the risk of bacterial contamination. But, chilled platelets (PLTs) show a reduced period in circulation due to the rapid clearance by hepatic cells or spleen macrophages after transfusion. The deleterious changes that PLTs undergo are mainly considered the result of PLT protein variation. However, the basis for proteomic variation of stored PLTs remains poorly understood. Besides count, activation markers (CD62P and Annexin V), and aggregation, we used quantitative mass spectrometry to create the first comprehensive and quantitative human PLT proteome of samples stored at different temperatures (22°C, 10°C and -80°C). We found different conditions caused different platelet storage lesion (PSL). PLT count was decreased no matter at what temperature stored. PLTs viability at low temperature dropped by 21.78% and 11.21%, respectively, as compared 10.26% at room temperature, there were no significant differences between the storage methods. Membrane expression of CD62P gradually increased in all groups especially stored at 22°C up to 40% and 10°C up to 30%. However, exposure of PS on the PLT membrane was below 1% in every group. The PLT proteome showed there were 575 and 454 potential proteins identified by general iTRAQ analysis and phosphorylation iTRAQ a nalysis, respectively, among them, 33 common differentially expressed proteins caused by storage time and 44 caused by storage temperature Especially, membrane-bound proteins (such as FERMT3, STX4, MYL9 and TAGLN2) played key roles in PLT storage lesion. The pathways "Endocytosis", "Fc gamma R-mediated phagocytosis" and "Regulation of actin cytoskeleton" were affected predominantly by storage time. And the pathways "SNARE interactions in vesicular transport" and "Vasopressin-regulated water reabsorption" were affected by cold storage in our study. Proteomic results can help us to understand PLT biochemistry and physiology and thus unravel the mechanisms of PSL in time and space for more successful PLT transfusion therapy.


Assuntos
Preservação de Sangue/métodos , Criopreservação/métodos , Agregação Plaquetária/fisiologia , Proteômica/métodos , Humanos , Temperatura
11.
Transfusion ; 55(1): 176-86, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25251668

RESUMO

BACKGROUND: The induction of hematopoietic stem cells to produce mass numbers of platelets (PLTs) in vitro is an effective method to address a lack of PLTs and PLT transfusion resistance in the clinic. However, the design of a low-cost and sustainable culture system is currently problematic. STUDY DESIGN AND METHODS: Here, the thrombopoietin, interleukin (IL)-6, and IL-11 genes, three regulatory factors important for thrombopoiesis, were used to construct self-splicing fusion genes linked by foot and mouth disease (F2A) and Theiler's murine encephalitis (T2A) viruses. Bone marrow stromal cells (BMSCs) transduced with the fusion gene acted as nourishing cells and induced cord blood mononuclear cells (MNCs) to generate PLTs in vitro. We counted these cells; determined the percentage of cells expressing specific cell surface markers (CD41); and measured their ability to aggregate via flow cytometry, immunohistochemical staining, and aggregation remote analyzer. RESULTS: BMSCs transduced with the fusion gene successfully induced cord blood MNCs to generate PLT-sized fragments in the absence of exogenous cytokines. The output was higher than that of the control groups, and the PLT-sized fragments were similar to endogenous PLTs in terms of shape, CD41 expression, and aggregation function. CONCLUSION: These results suggest that our method could be used to develop a low-cost sustainable cultivation system that generates PLTs in vitro by enhancing the autocrine production of related cytokines through the nourishment provided by cells transduced with a syncretic gene.


Assuntos
Plaquetas/citologia , Sangue Fetal/citologia , Genes Sintéticos , Interleucina-11/metabolismo , Interleucina-6/metabolismo , Leucócitos Mononucleares/citologia , Células Estromais/citologia , Trombopoese , Trombopoetina/metabolismo , Adenoviridae/genética , Sequência de Bases , Células Cultivadas , Técnicas de Cocultura , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Vírus da Febre Aftosa/genética , Vetores Genéticos/genética , Humanos , Interleucina-11/genética , Interleucina-6/genética , Dados de Sequência Molecular , Biossíntese de Proteínas , Células Estromais/metabolismo , Theilovirus/genética , Trombopoetina/genética , Transdução Genética
12.
Biomater Sci ; 12(5): 1281-1293, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38252410

RESUMO

Acute liver injury (ALI) is a highly fatal condition characterized by sudden massive necrosis of liver cells, inflammation, and impaired coagulation function. Currently, the primary clinical approach for managing ALI involves symptom management based on the underlying causes. The association between excessive reactive oxygen species originating from macrophages and acute liver injury is noteworthy. Therefore, we designed a novel nanoscale phase variant contrast agent, denoted as PFP@CeO2@Lips, which effectively scavenges reactive oxygen species, and enables visualization through low intensity pulsed ultrasound activation. The efficacy of the nanoparticles in scavenging excess reactive oxygen species from RAW264.7 and protective AML12 cells has been demonstrated through in vitro and in vivo experiments. Additionally, these nanoparticles have shown a protective effect against LPS/D-GalN attack in C57BL/6J mice. Furthermore, when exposed to LIPUS irritation, the nanoparticles undergo liquid-gas phase transition and enable ultrasound imaging.


Assuntos
Fígado , Nanopartículas , Camundongos , Animais , Espécies Reativas de Oxigênio , Camundongos Endogâmicos C57BL , Fígado/diagnóstico por imagem , Inflamação , Ondas Ultrassônicas
13.
Dis Markers ; 2023: 6072782, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37124944

RESUMO

EPAS1 plays an important role in the development and progression of multiple tumor types by interacting with a series of other molecules. However, the prognostic and diagnostic values of EPAS1 in acute myeloid leukemia (AML) remain unknown. Here, we systematically explored and clarified the potential functions of EPAS1 in AML using data from Xena Browser and TCGA database. The expression of EPAS1 was significantly lower in AML patients than that in healthy people. The GO, KEGG, GSEA, and GSVA were performed to explore the potential functions and signaling pathways. The survival analysis was conducted using Cox regression analysis and the Kaplan-Meier method. Immune cell infiltration was evaluated via single-sample GSEA (ssGSEA). The results of enrichment analyses suggested that low-EPAS1 expression was related to the initiation, development, and prognosis of AML. The immune microenvironment landscape in AML was described by ssGSEA. ROC analysis of EPAS1 showed high discrimination ability between AML patients and healthy people. Kaplan-Meier method indicated that low-EPAS1 expression correlated significantly with a poor overall survival. Multivariate Cox regression analysis revealed that both age and EPAS1 expression were independent prognostic factors in AML patients. Furthermore, the nomogram based on these two variables performed well in discrimination and calibration. In summary, our study may provide new insights into the molecular mechanisms underlying AML and demonstrate the diagnostic and prognostic value of EPAS1 in AML for the first time.


Assuntos
Biologia Computacional , Leucemia Mieloide Aguda , Humanos , Prognóstico , Bases de Dados Factuais , Leucemia Mieloide Aguda/genética , Análise Multivariada , Microambiente Tumoral
14.
Medicine (Baltimore) ; 102(43): e35700, 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37904366

RESUMO

RATIONALE: Female genital tract abnormalities are relatively uncommon and usually discovered accidentally. And hymen prolapse is even rarer, which is asymptomatic and is commonly found during the examination of the baby external genitals. PATIENT CONCERNS: Here, we report a case of fetal genital abnormality detected at 32 weeks of gestation. DIAGNOSES: At 32+1 weeks of pregnancy, ultrasound showed taht an iso-echoic mass of about 8 mm × 5 mm was protruding from the genitalia, and at 36 weeks, ultrasound showed that an iso-echoic mass of about 9 mm × 5 mm could be seen protruding from the genitalia, and its morphology was similar to the result of the 32-week data. At 39 weeks a baby girl was naturally delivered. Physical examination showed the female external genitalia, part of the hymen protruded into the vaginal orifice. Finally, the clinical diagnosis was hymen prolapse. INTERVENTIONS AND OUTCOMES: No treatment was carried out. Reexamination at 11 days after birth revealed a significantly smaller prolapse than before. Since the postpartum follow-up, the baby has been in good condition, the hymen has gradually returned, and the genitals are all normal. LESSONS: Regardless of the confidentiality of prenatal tests regarding the sex of the fetus, prenatal ultrasound should be used to fully evaluate the morphology and structure of each system including the reproductive system of the fetus when screening fetal malformations. The purpose of this case is to remind doctors of the rigorous degree of genital examination, increase the detection rate, and save the life of the fetus.


Assuntos
Hímen , Diagnóstico Pré-Natal , Gravidez , Feminino , Humanos , Hímen/anormalidades , Feto/diagnóstico por imagem , Vagina , Prolapso , Ultrassonografia Pré-Natal
15.
J Contemp Brachytherapy ; 15(2): 134-140, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37215613

RESUMO

Purpose: The purpose of this study was to investigate the precision of deep learning (DL)-based auto-reconstruction in localizing interstitial needles in post-operative cervical cancer brachytherapy (BT) using three-dimensional (3D) computed tomography (CT) images. Material and methods: A convolutional neural network (CNN) was developed and presented for automatic reconstruction of interstitial needles. Data of 70 post-operative cervical cancer patients who received CT-based BT were used to train and test this DL model. All patients were treated with three metallic needles. Dice similarity coefficient (DSC), 95% Hausdorff distance (95% HD), and Jaccard coefficient (JC) were applied to evaluate the geometric accuracy of auto-reconstruction for each needle. Dose-volume indexes (DVI) between manual and automatic methods were used to analyze the dosimetric difference. Correlation between geometric metrics and dosimetric difference was evaluated using Spearman correlation analysis. Results: The mean DSC values of DL-based model were 0.88, 0.89, and 0.90 for three metallic needles. Wilcoxon signed-rank test indicated no significant dosimetric differences in all BT planning structures between manual and automatic reconstruction methods (p > 0.05). Spearman correlation analysis demonstrated weak link between geometric metrics and dosimetry differences. Conclusions: DL-based reconstruction method can be used to precisely localize the interstitial needles in 3D-CT images. The proposed automatic approach could improve the consistency of treatment planning for post-operative cervical cancer brachytherapy.

16.
Dalton Trans ; 51(29): 11072-11085, 2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35796202

RESUMO

The uranium metallacyclocumulene, [η5-1,3-(Me3Si)2C5H3]2U(η4-C4Ph2) (3) was isolated from the reaction mixture containing [η5-1,3-(Me3Si)2C5H3]2UCl2 (1), potassium graphite (KC8) and 1,4-diphenylbutadiyne (PhCC-CCPh) in good yield. The reactivity of 3 towards various small organic molecules was evaluated. For example, while complex 3 shows no reactivity towards alkynes and 2,2'-bipyridine, it may deliver the [η5-1,3-(Me3Si)2C5H3]2U(II) fragment in the presence of Ph2E2 (E = S, Se) and Ph3CN3, or react as a nucleophile in the presence of carbodiimides, isothiocyanates, aldehydes, ketones, and pyridine derivatives, forming five-, seven- or nine-membered heterometallacycles. On the contrary, addition of Ph2CS to 3 induces CS bond cleavage yielding the dithiolate complex [η5-1,3-(Me3Si)2C5H3]2U[S2(C12H5Ph5)] (14). In contrast, the closely related, but sterically more encumbered uranium metallacyclocumulene [η5-1,2,4-(Me3Si)3C5H2]2U(η4-C4Ph2) (4) features a more limited reactivity which is restricted to mono- and double insertions with small unsaturated organic molecules such as isothiocyanates, ketones and nitriles.

17.
Acta Biomater ; 151: 118-133, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36028196

RESUMO

Platelets play vital roles in vascular repair, especially in primary hemostasis, and have been widely used in transfusion to prevent bleeding or manage active bleeding. Recently, platelets have been used in tissue repair (e.g., bone, skin, and dental alveolar tissue) and cell engineering as drug delivery carriers. However, the biomedical applications of platelets have been associated with platelet storage lesions (PSLs), resulting in poor clinical outcomes with reduced recovery, survival, and hemostatic function after transfusion. Accumulating evidence has shown that biophysical cues play important roles in platelet lesions, such as granule secretion caused by shear stress, adhesion affected by substrate stiffness, and apoptosis caused by low temperature. This review summarizes four major biophysical cues (i.e., shear stress, substrate stiffness, hydrostatic pressure, and thermal microenvironment) involved in the platelet preparation and storage processes, and discusses how they may synergistically induce PSLs such as platelet shape change, activation, apoptosis and clearance. We also review emerging methods for studying these biophysical cues in vitro and existing strategies targeting biophysical cues for mitigating PSLs. We conclude with a perspective on the future direction of biophysics-based strategies for inhibiting PSLs. STATEMENT OF SIGNIFICANCE: Platelet storage lesions (PSLs) involve a series of structural and functional changes. It has long been accepted that PSLs are initiated by biochemical cues. Our manuscript is the first to propose four major biophysical cues (shear stress, substrate stiffness, hydrostatic pressure, and thermal microenvironment) that platelets experience in each operation step during platelet preparation and storage processes in vitro, which may synergistically contribute to PSLs. We first clarify these biophysical cues and how they induce PSLs. Strategies targeting each biophysical cue to improve PSLs are also summarized. Our review is designed to draw the attention from a broad range of audience, including clinical doctors, biologists, physical scientists, engineers and materials scientists, and immunologist, who study on platelets physiology and pathology.


Assuntos
Plaquetas , Hemostáticos , Biofísica , Plaquetas/metabolismo , Sinais (Psicologia) , Hemostasia , Hemostáticos/farmacologia
18.
Gastroenterol Res Pract ; 2022: 7944849, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35873352

RESUMO

Purpose: Peptic ulcer is a multifactorial and complex disease and affects a wide range of people worldwide. We provided a novel therapeutic approach for peptic ulcer and observed its effect. Methods: Peptic ulcer patients were enrolled from 2016 to 2017 in Chongqing and randomly assigned to two groups: a control group that used only rabeprazole and a platelet-rich plasma (PRP) group that received a combination therapy of autologous PRP (aPRP) and rabeprazole. The therapeutic effect was assessed via the ulcer size and symptom score. Results: A total of 27 patients were included (12 patients in the control group and 15 patients in the PRP group) in this study. Our results showed that all participants have healed in 30 days, and there was no significant difference in healing time between the PRP group and the control group in different independent variables. However, regression analysis revealed that the healing time was 6.99 days shorter in the PRP group than that in the control group, and patients with higher symptom scores in the initial examination need more time to heal during treatment. Endoscopic results showed that the repaired ulcer in the PRP group was more similar to the normal gastric mucosa tissue than that the control group. Conclusion: This study showed an encouraging preliminary result that aPRP has a positive result in patients with peptic ulcer and seems to be a better choice for refractory peptic ulcer treatment. Although further follow-up studies are needed to determine the duration of efficacy of aPRP, the approach will be helpful in improving the clinical treatment of peptic ulcer.

19.
Dalton Trans ; 50(36): 12502-12516, 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34342314

RESUMO

This paper describes the synthesis and reactivity of [η5-1,3-(Me3Si)2C5H3]2U(P-2,4,6-iPr3C6H2)(OPMe3) (6) which is accessible from a ligand exchange reaction between [η5-1,3-(Me3Si)2C5H3]2U(P-2,4,6-iPr3C6H2)(OPPh3) (2) and Me3PO at ambient temperature. Phosphinidene 6 exhibits no reactivity towards internal alkynes, but readily reacts with various hetero-unsaturated molecules such as isothiocyanates, aldehydes, nitriles, isonitriles, and organic azides, forming uranium sulfido, oxido, imido, and uranaheterocyclic compounds. Nevertheless, with the bidentate ortho-dicyanobenzene o-C6H4(CN)2 the zwitterionic species [η5-1,3-(Me3Si)2C5H3]2U[NHC(N){C6H4CP(2,4,6-iPr3C6H2)CH2PMe2O}] (13) is isolated in good yield. Moreover, 6 converts with Ph2S2 to the uranium(III) phenylthiolate compound [η5-1,3-(Me3Si)2C5H3]2USPh(OPMe3) (7) in good isolated yield. Furthermore, the influence of the Lewis base on the reactivity of the uranium phosphinidene metallocenes has also been evaluated.

20.
Dalton Trans ; 50(24): 8349-8363, 2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34037037

RESUMO

The Lewis base supported terminal uranium phosphinidene metallocene [η5-1,3-(Me3C)2C5H3]2U([double bond, length as m-dash]P-2,4,6-iPr3C6H2)(OPMe3) (2) could be isolated from a salt metathesis reaction in toluene at ambient temperature between [η5-1,3-(Me3C)2C5H3]2U(Cl)Me (1) and 2,4,6-iPr3C6H2PHK in the presence of Me3PO, and its structure and reactivity were probed in detail. No reaction of 2 with internal alkynes was observed, but it reacts in the presence of various heterounsaturated molecules such as CS2, isothiocyanates, aldehydes, imines, diazenes, carbodiimides, nitriles, isonitriles, diazoalkane, and organic azides, forming carbodithioates, sulfidos, oxidos, metallaheterocycles, and imido complexes, in good yields. Moreover, on reaction with the diazoalkane derivative Me3SiCHN2 the pseudophosphinimido uranium(iii) complex [η5-1,3-(Me3C)2C5H3]2U(N[double bond, length as m-dash]P-2,4,6-iPr3C6H2)(OPMe3) (20) can be isolated in good yield.

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